Apparatus for completion and working over of wells



1964 R. S..RUGELEY ETAL 3,116,781

APPARATUS FOR COMPLETION AND WORKING OVER OF WELLS Filed March 29. 1961 2E U L 0 LO muw VU m SH m mu EN BE OK R 3,116,781 APPARATUS FOR COMPLETION AND WORKING OVER OF WELLS Robert S. Rugeley and Kenneth C. Woolley, Houston,

Tex asslgnors, by meme assignments, to Jersey Produetion Research Company, Tulsa, Okla., a corporation of Delaware Filed Mar. 29, 1961, Ser. No. 99,243 5 Claims. Cl. 153-54) The present invention is directed to apparatus for completion and working over of wells. More particularly. the invention is concerned with apparatus for employment of a continuous length of coiled tubing in well completion and a workover operations. In its more specific aspects, the invention is concerned with apparatus in which a coiled tubing is straightened and run into a well under pressure for use in flowing a fluid therethrough.

The invention comprises apparatus for use in a well in completion and workover operations which comprise a rotatably mounted reel adapted to receive a continuous length of coiled substantially rigid or inflexible tubing. Spaced horizontally from and rotatably mounted in operational relationship to the reel is a large grooved first drum which is adapted to receive the tubing in the groove thereon. Guide means are provided between the reel and the first drum to guide the coiled tubing onto the grooved drum. The grooved first drum has operatively connected thereto for rotation with the first drum in a direction opposite to the rotation of the first drum a plurality of grooved smaller drums which are peripherally spaced apart on the first drum. Rotatably mounted, vertically spaced from the plurality of drums and spaced apart a suflicient distance to allow passage of the tubing are a plurality of grooved rollers. Power means such as a hydraulic motor is opcrativeiy connected to the first drum for rotating the first drum such that a suflicient force is applied by the drums and the rollers to straighten the tubing. The grooves on the several drums are aligned for carrying the coiled tubing between the straightening rollers.

The present invention will be further described with respect to the drawing in which:

FlG. l is an isometric view of a preferred embodiment for uncoiling the coiled tubing, straightening it, and then forcing it into the well, while PK]. 2 is a partial cross-sectional view of a well having the straightened tubing run thereinto.

Referring now to the drawing which represents a preferred embodiment and particularly to FIG. 1, numeral 1! designates a suitable support such as the bed of a truck on which is arranged a reel or spool 12 having an axle 13 carried by a yoke 14. Arranged on the reel or spool 12 is a coil 15 of substantially rigid or inflexible tubing. The support or truck bed 11 has a platform 16 arranged on upstanding supports 16a which may be several in number, the platform protruding from the sup port 11 such that it may be positioned adjacent wellhead l7. Mounted on the platform 16 is a yoke 18 which carries on axle 19 a large first drum 20 and which carries on axles 21a, 21b, 21c and 21d, a plurality of smaller drums 22, 23, 24 and 25, respectively, with grooves 22a, 22b, 22c and 22d, which are aligned with groove 20a to engage with the tubing 15. Guide means, such as block 26, guides the tubing 15 onto drum 20 to fit in groove 20a. Means 26 may be carried by a yoke 27 mounted on yoke 18. The drum 20 has attached thereto or has formed thereon a gear 28 which meshes with a gear 29'carried on shaft 30 and which is connected to a power means such as a hydraulic motor 31. The gear 28 meshes with gears 22b, 23b, 24b and b of drums 22, 23, 24 and 25, respectively, to cause drums 22, 23, 24 and 25 to rotate 3,116,781 Patented Jan. 7, 1964 in a direction opposite to the rotation of drum 20 on operation of the power means 31. The tubing 15 is carried over the drum 20 and under the drums 22, 23, 24 and 25 and then is caused to pass between the straightening rollers 34 and 35 which are rotatably mounted by axles 36 and 37 on yoke 38 which is attached to the platform 16.

Passage of the tubing 15 over the drum 20 and under the drums 22, 23, 24 and 25 and between the rollers 34 and 35 which are spaced apart a sufficient distance such that the grooves 340 and 350 will accommodate passage of the straightened tubing 15 between the rollers 34 and 35 causes the straightened tubing 15 to be forced downwardly. The straightened tubing propelled by drum 20 through the rollers 34 and 35 is then forced through the opening 40 of the wellhead 17 which is provided with valves 41 and 42 and a flow line 43 provided with a valve 44. This force or pressure is exerted by drum 20 on the straightened pipe. The wellhead 17 is connected into the well 45} as shown'in FIG. 2. which may suitably be cased with a casing 46. The well 45 is under pressure and is suitably closed in with a closure means 47 attached to the wellhead 17. The well 45 pierces aplurality of subsurface earth strata, sands. intervals, zones or formations 48, 49, and 50, which may contain hydrocarbons or other valuable earth fluids such as gas, crude petroleum, helium, and the like. The casing 46 has been pierced in interval 50 to form perforations 51 through which hydrocarbons may flow into the casing 46, thence to the wellhead eithcr through the tubing 15 or through the annulus 52 and thence by way of flow line 43 to suitable storage as may be desired. The straightened tubing 15 is sealed in the opening 40 and may have connected thereto control means. not shown. such as a valve such that the straightened continuous tubing 15 may be used for injection of fluid, for example, into any of the subsurface formations as may be desired. it may be expedient to seal the perforations 51 and this may be accomplished by lowering the tubing 15 to the region of the perforations Stand flowing a slurry of a fluid such as a slurry of cementitious material in a fluid condition; excess ccmentitious material may be removed by reverse circulation with fluid flowing down through the flow line 43, the annulus 52. and up through the tubing 15 to the earths surface. Other well completion fluids such as emulsions, stimulating agents, liquids. gases. surface active agents. and the like, such as acids, fluid containing corrosion inhibitors, and other servicing fluids such as fracturing fluids, and the like may be employed.

Thus. the present invention enables the accomplishment of 'well completion and \vorkover and servicing operations by utilizing coiled tubing instead of the jointed tubing evhich is currently in use. The coiled tubing is wound on a spool or reel and is then uncoiled into the well as has been described and then may be retrieved and reused. Alternately. the tubing may be left in the well to facilitate operations which may occur frequently such as the injection of hot oil or corrosion inhibitor. Likewise, the tubing may be left in the well for use permanently as a production tubing or for control of the well.

in the present invention, a continuous length of coiled tubing is utilized and apparatus is provided to remove the tubing from the coil and straighten it for running into a well under pressure. The tubing is secured while running in, removing, or in a stationary position and the coiled tubing is straightened for use in the well such that undue friction loads against the sides of the casing or tubing in the well are not produced.

In the apparatus of the present invention, the large drum with the smaller drums carried thereon provide means for holding or lifting the tubing while the rollers which rotate freely straighten the tubing as it comes off 3 the large drum. The small drums force the straightened tubing into the well.

The number of peripherally arranged drums may be two or more. While one drum may be used, it is desirable to provide a plurality of peripherally arranged drums. Likewise, a plurality of pairs of straightening rollers may be used with the straightening rollers spaced vertically below the peripherally carried drums.

It is necesary to provide a suitable resilient seal such as 53 between the tubing 15 and the well-head 17 as the tubing 15 enters the opening 40 such that the well may be maintained under pressu e.

it is also necessary in the present invention that force be applied to the straightened tubing adjacent the wellhead sufficient to force the straightened tubing into the well. This force must be applied to the straightened tubing about 12 inches from the wellhead for satisfactory results. This force or pressure may be an amount from about 10% to about 25% greater than the pressure of the well. If the force is applied otherwise to the tubing, then the tubing will corkscrew and not enter the pressurized well.

The amount of pressure on the well will ordinarily be formation pressure which may range from about 50 to about 7000 pounds per square inch. Since the well is under pressure, once the casing has been perforated into a hydrocarbon producing zone, such as an oil or gas strata, to inject fluids into such zones, it will be necessary to cmploy a pressure greater than formation pressure down through the continuous tubing on the fluid to be injected or introduced into the well.

The large drum is suitably sized to provide a large area of contact with the tubing while the smaller drums provide a small area of contact. The large drum has a diameter in the range from about 5 to about times the diameter of the smaller drums to provide the necessary area of contact. Thus, the large drum may have a diamcter measured from the bottom of the groove of about 35.25 inches; whereas, the smaller drums each may have a diameter measured from the bottom of the groove of about 5.29 inches. The gear on the large drum may be about 36 inches in diameter while the gears on the smaller drums may have a diameter about 6 inches. The smaller drums are suitably mounted on the large drum to provide an angle measured from the center of the large drum of about 60'.

in a specific embodiment with one large and four small drums of a size indicated the contact area of the large drum with tubing of inch in outside diameter is about 2l.962 square inches; whereas, the four smaller drums provide a total contact area of 0.28 square inch, the contact area of each of the smaller drums being 0.070 square inch.

The grooves on the several drums must be of size to accommodate the tubing for passage between the several drums. These grooves may have a depth for 3.4 inch tubing of about 0.323 inch.

The apparatus of the present invention is quite advantageous and useful in that wells may be completed and serviced using a continuous tubing string which may suitably be arranged in a coil eliminating most of the manpower ordinarily used and also eliminating the necessity of using numerous lengths of pipe which heretofore has been a tremendous problem in handling same. An unexpected and u-nobvious advantage of the present invention by virtue of the particular embodiment is the minimizing of flexing stress or fatigue in the continuous tubing string. Thus, the tubing may be uncoilcd, straightened and forced into a well and removed therefrom and coiled on and uncoiled from the reel many times without fatigue causing destruction or breaking of the tubing.

The nature and objects of the present invention having been completely described and illustrated, what we wish to claim as new and useful and secure by Letters Patent 1. Apparatus for running tubing in a well under pressure which comprises a rotatably mounted reel adapted to receive a continuous length of coiled substantially inflexible tubing, a grooved first drum spaced horizontally from and rotatably mounted in operative relationship to said reel to receive said tubing in the groove thereon, a plurality of grooved drums peripherally spaced apart on and operatively connected to said first drum for rotation therewith in a direction opposite to the rotation of said first drum, a pair of grooved rollers freely rotatably mounted in tandem vertically spaced from said plurality of drums and spaced apart a suflieient distance such that the grooves on said rollers allow passage of said tubing, and pow .r means operatively connected to said first drum for rotating said first drum, the grooves on said drums being aligned for carrying said coiled tubing between said rollers and forcing said tubing into said avcll.

2. Apparatus for running tubing in a well under pressure which comprises a rotatably mounted reel adapted to receive a continuous length of coiled substantially inflexible tubing, a grooved first drum spaced horizontally from and rotatably mounted in operative relationship to said reel to receive said tubing in the groove thereon. guide means for guiding said coiled tubing onto said grooved first drum, a plurality of grooved drums peripherally spaced apart on and operatively connected to said first drum for rotation therewith in a direc:ion opposite to the rotation of said first drum, :1 pair of grooved rollers freely rotatably mounted in tandem vertically spaced from said plurality of drums and spaced apart a sufiicient distance such that the grooves on said rollers allow passage of said tubing. and power means operatively connected to said firstdrurn for rotating said first drum, the grooves on said drums being aligned for carrying said coiled tubing between said rollers and forcing said tubing into said well.

3. Apparatus for running tubing in a well under pressure which comprises a rotatably mounted reel, a continuous length of substantially inflexible tubing coiled on said reel, a grooved first drum spaced horizontally from and rotatably mounted in operative relationship to said reel to receive said tubing in the groove thereon; guide means for guiding said coiled tubing onto said grooved first drum, a plurality of grooved drums peripherally spaced apart on and operatively connected to said first drum for rotation therewith in a direction opposite to the rotation of said first drum, a pair of grooved rollers freely rotatably mounted in tandem vertically spaced from said plurality of drums and spaced apart a suliicient distance such that the grooves on said rollers allow passage of said tubing, and power means operatively connected to said first drum for rotating said first drum, said first drum having a diameter in the range from about 5 to about 10 times the diameter of said plurality of drums, the grooves on said drums being aligned for carrying said coiled tubing between said rollers and forcing said tubing into said well.

4. Apparatus for running tubing in a well under pressure which comprises a rotatably mounted reel adapted to receive a continuous length of coiled substantially in flexible tubing, a grooved first drum spaced horizontally from and rotatably mounted in operative relationship to said reel to receive said tubing in the groove thereon, guide means for guiding said coiled tubing onto said grooved first drum, grooved sccond third, fourth, and fifth drums peripherally spaced apart on said first drum, means operalively connecting said second, third, fourth. and fifth drums to said first drum for rotation therewith in a direction opposite to the rotation of said first drum, a pair of grooved rollers freely rotatably mounted in tandem vertically spaced from said second. third. fourth and fifth drums and spaced apart a sutlieient distance such that the grooves on said rollers allow passage of said tubing. and power means operatively connected to said first drum for rotating said first drum, the diameter of said second. third, fourth, and fifth drums being substantially equal and the diameter of said first drum being in the range from about 5 to about 10 times the diameter of said second, third, fourth, and fifth drums, the grooves on said drums being aligned for carrying said coiled tubing between said rollers and forcing said tubing into said well.

5. Apparatus in according with claim 4 in which said operatively connecting means comprise meshing gears on said drums.

References Cited in the file of this patent UNITED STATES PATENTS 

1. APPARATUS FOR RUNNING TUBING IN A WELL UNDER PRESSURE WHICH COMPRISES A ROTATABLY MOUNTED REEL ADAPTED TO RECEIVE A CONTINUOUS LENGTH OF COILED SUBSTANTIALLY INFLEXIBLE TUBING, A GROOVED FIRST DRUM SPACED HORIZONTALLY FROM AND ROTATABLY MOUNTED IN OPERATIVE RELATIONSHIP TO SAID REEL TO RECEIVE SAID TUBING IN THE GROOVE THEREON, A PLURALITY OF GROOVED DRUMS PERIPHERALLY SPACED APART ON AND OPERATIVELY CONNECTED TO SAID FIRST DRUM FOR ROTATION THEREWITH IN A DIRECTION OPPOSITE TO THE ROTATION OF SAID FIRST DRUM, A PAIR OF GROOVED ROLLERS FREELY ROTATABLY MOUNTED IN TANDEM VERTICALLY SPACED FROM SAID PLURALITY OF DRUMS AND SPACED APART A SUFFICIENT DISTANCE SUCH THAT THE GROOVES ON SAID ROLLERS ALLOW PASSAGE OF SAID TUBING, AND POWER MEANS OPERATIVELY CONNECTED TO SAID FIRST DRUM FOR ROTATING SAID FIRST DRUM, THE GROOVES ON SAID DRUMS 